Research will be directed along two main paths: (1) Investigations into molecular structure and obsolute configurations of some cyclophosphamide derivatives will be pursued. Two groups of isomeric compounds synthesized in Japan and in Alabama will be analyzed in order to obtain information on the stereochemical pathways of cyclophosphamide activation. (2) Crystal structure analysis of folic acid agonists and antagonists will be undertaken in order to identify parameters useful for the design of new antifolate cancer drugs. In addition, studies on other anticancer drugs will also be begun.